CVE-2021-3987

mediumpriority · track · 17OT risk · elevatedEPSS 0.003 · 28 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.35% (28th) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the `create_shelf` method in `shelf.py` not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users.

cvss

Technical severity, 0–10. One row per scoring source.

5.4

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 1.4

v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · ENISA EU

v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · security@huntr.devexploitability 2.8 · impact 2.5

v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · OSV

v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-862USprimaryCWE-284USCWE-284USCWE-862US

affected products (3)

Products and version ranges known to be affected.

janeczku janeczku/calibre-web≤ unspecified ≤latestenisa_euvdEU
janeczku calibre-web< 0.6.15nvdUScpe:2.3:a:janeczku:calibre-web:*:*:*:*:*:*:*:*
PyPI calibreweb< 0.6.15osvUSpkg:pypi/calibreweb

advisories (2)

Vendor and ecosystem advisories describing this.

GHSA-fj5v-w2jp-wqvjImproper Access Control in janeczku/calibre-web2024-11-15ghsa · osvUS
An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the `create_shelf` method in `shelf.py` not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users.
PYSEC-2026-1229Improper Access Control in janeczku/calibre-web2026-07-07vendor · osvUS
An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the `create_shelf` method in `shelf.py` not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2024-11-15modified 2026-06-17

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+11490 more

references (6)

External citations — patches, advisories, analysis.

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